Quick-lock driver for a bone screw

Abstract

A driver instrument for engaging and transferring rotational torque to a bone screw assembly which includes a shaft and sleeve adapted to engage and couple the bone screw assembly into a single coaxial unit while the bone screw assembly is being driven into a bone and then to release the bone screw assembly from the driver instrument. The driver instrument includes an elongate shaft, a sleeve, and bone screw assembly engaging features on the elongate shaft and/or the sleeve.

What is claimed is: 
     
         1 . A driver instrument adapted to engage and drive bone screw assemblies which include a bone screw and an associated housing, said driver instrument comprising:
 an elongate shaft having a proximal end and a distal end, the distal end further comprising:
 a driver engagement feature adapted to engage and rotationally drive a head of a bone screw and 
 one or more lugs protruding radially therefrom, 
 said one or more lugs being adapted to engage a housing of a bone screw assembly to limit axial rotation thereof relative to said elongate shaft; and 
   a sleeve having a proximal end, a distal end, and being adapted for coaxial rotation about a common longitudinal axis with the elongate shaft,   wherein the distal end of the sleeve includes an engagement feature adapted to rotationally engage a mating engagement feature of the housing of a bone screw assembly.   
     
     
         2 . The driver instrument of  claim 1 , wherein the engagement feature of the sleeve includes one or more radial projections extending circumferentially at least partially around the sleeve and adapted to engage the mating engagement feature of the housing of the bone screw assembly. 
     
     
         3 . The driver instrument of  claim 2 , wherein the mating engagement feature of the housing of the bone screw assembly is grooves of a threaded opening of the housing. 
     
     
         4 . The driver instrument of  claim 1 , wherein the engagement feature of the sleeve includes one or more grooves extending circumferentially at least partially around the sleeve and adapted to engage a mating engagement feature of the housing of the bone screw assembly. 
     
     
         5 . The driver instrument of  claim 4 , wherein the mating engagement feature of the housing of the bone screw assembly is threads of a threaded opening of the housing as the mating engagement feature. 
     
     
         6 . The driver instrument of  claim 1 , wherein the proximal end of the sleeve includes a sleeve handle adapted to selectably couple to the elongate shaft to limit relative rotation therebetween about the common longitudinal axis. 
     
     
         7 . The driver instrument of  claim 6 , wherein the sleeve handle adapted to selectably couple to the elongate shaft includes a button associated with the sleeve handle, said button having a first position in which the sleeve handle is rotationally coupled to the elongate shaft and a second position in which the sleeve handle and the elongate shaft are decoupled such that the sleeve handle may be rotated relative to the elongate shaft. 
     
     
         8 . The driver instrument of  claim 1 , wherein the elongate shaft includes a tapered distal tip adapted to facilitate insertion of the driver engagement feature into the head of the bone screw. 
     
     
         9 . The driver instrument of  claim 1 , wherein the proximal end of the elongate shaft further comprises a handle. 
     
     
         10 . The driver instrument of  claim 9 , wherein the handle is removably coupled to the proximal end of the elongate shaft with a quick-connect feature. 
     
     
         11 . The driver instrument of  claim 1 , wherein the engagement feature of the sleeve lies in a plane transverse to the common longitudinal axis of the driver instrument. 
     
     
         12 . The driver instrument of  claim 1 , wherein the engagement feature of the sleeve lies in a plane substantially perpendicular to a longitudinal axis of the housing. 
     
     
         13 . The driver instrument of  claim 1 , wherein the engagement feature of the sleeve lies in one or more planes which are tilted relative to a longitudinal axis of the housing. 
     
     
         14 . The driver instrument of  claim 1 , wherein rotation of the engagement feature of the sleeve relative to the mating engagement feature of the housing tends to advance a distal tip of the elongate shaft into a driver socket of the bone screw assembly. 
     
     
         15 . A method of engaging and a driver instrument with a bone screw assembly comprising:
 inserting a distal tip of a driver instrument having an elongate shaft including a driver engagement feature into a driver socket of a bone screw of a bone screw assembly;   inserting one or more lugs of the elongate shaft into mating channels of a housing of the bone screw assembly, wherein inserting one or more lugs of the elongate shaft into mating channels of the housing of the bone screw assembly limits rotation of the housing relative to the elongate shaft;   inserting a sleeve coaxially disposed about the elongate shaft into the housing of the bone screw assembly with the sleeve in a first position, said sleeve including an engagement feature being adapted to rotationally engage a mating engagement feature of the housing of the bone screw assembly; and   rotating the sleeve relative to the elongate shaft and the housing of the bone screw assembly to a second position while positioned in the housing of the bone screw assembly, wherein upon relative rotation of the sleeve with respect to the elongate shaft, the engagement feature of the sleeve couples with the mating engagement feature of the housing of the bone screw assembly.   
     
     
         16 . The method of  claim 15 , wherein the engagement feature comprises one or more projections and the mating engagement feature comprises one or more grooves. 
     
     
         17 . The method of  claim 15 , wherein the engagement feature comprises one or more grooves and the mating engagement feature comprises one or more projections. 
     
     
         18 . The method of  claim 15 , wherein the engagement feature is adapted to engage a threaded region within the housing of the bone screw assembly and the threaded region of the bone screw assembly provides the mating engagement feature. 
     
     
         19 . The method of  claim 15 , further comprising:
 decoupling the elongate shaft from the sleeve prior to the rotating step to rotationally decouple the elongate shaft from the sleeve.   
     
     
         20 . The method of  claim 15 , further comprising:
 locking the sleeve from rotational movement relative to the elongate shaft in the second position.